Automatic fuel dispensing nozzle

ABSTRACT

A valved fuel dispensing nozzle with a lockout plunger which is unlocked to release the valve in response to the action of a vacuum signal on a diaphragm, resulting from the rise of fluid about the spout wherein a second diaphragm is also connected to unlock the lockout plunger in response to a predetermined rise of pressure within the fuel tank.

United States Patent 1191 Mayer Nov. 13, 1973 [54] AUTOMATIC FUELDISPENSING NOZZLE 3,018,136 H1962 Williams 251/14 X 3,253,611 5/1966Cummns... 251/14 X [75] Invent Edward Mayer Newburgh 3,586,073 6/1971Vest 141/128 [73] Assignee: Texaco, Inc., New York, NY.

Primary Examiner-Wayne A. Morse, Jr. [22] Filed 1971 Attorney-Thomas H.Whaley et al. [21] Appl. No.: 185,998

[57] ABSTRACT [52 0.8. CI. 141/128, 251/14 Avalved fuel dispensingnozzle with a lockout Plunger [51] Int. Cl... B67d 5/04, B67d 5/377 16k31/145 which is unlocked to release the valve in response to [58] Fieldof Search 141/128, 5; 251/14 the action of a vacuum Signal on a p gresulting from the rise of fluid about the spout wherein a [56] Refe ene Ci second diaphragm is also connected to unlock the UNITED STATESPATENTS lockout plunger in response to a predetermined rise of 3,586,0696/1971 Vest 141/128 x pressure wlthm the fuel tank 3.586,070 6/1971Daniels 141/128 4 Claims, 4 Drawing Figures 54 9 4 40 62 36 4 20 l 34 65a 52 I 22 1s 48 1- 4 5 .cssc. 2L 32 I {/0 l2 l 2 44 63 24 ,J 1, 26 Q)60 I x4 2 I .2 6 '4 2a 3o Patented Nov. 13, 1973 3,771,575

2 Sheets-Sh0et l Patented 'Nov. 13, 1973 I 3,771,575

2 Sheets-Sheet 2 FIG. 3

FIG. 2

AUTOMATIC FUEL DISPENSING NOZZLE The present invention relates to a fueldispensing nozzle and more particularly to an automatic flow controlnozzle.

It is the primary objective of the present invention to provide a nozzleas above, which is repsponsive to overpressure in the fuel tank to cutoff automatically, thereby to prevent damage to a vehicle fuel tank, forexample.

Heretofore it has become a matter of almost universal convention toprovide each fuel dispensing nozzle with a vacuum signal, responsive,lockout plunger associated with the lever controlling the main flowvalve of the nozzle. A venturi source associated with the interior ofthe nozzle normally tends to set up. a vacuum which is continuouslyrelieved or vented by a pressure tap downstream near the tip of thenozzle spout.

When, however, asudden back-surge of liquid fuel immerses this tap orvent, the internal vacuum signal rises, releasing the lockout plungerand terminating the operation of the nozzle. The present invention, onthe other hand, contemplates operation in connection with a vehiclefueling system which is presumably forthcoming, in which the nozzlemakes tight or sealing engagement with the inlet pipe of the fuel tank.

While the present invention does not undertake to predict what form theprospective sealed vehicle fueling system will take and what means willbe employed to vent or relieve the tank pressures due to the influx offuel delivered by the nozzle, it is obvious that venting will have to berealized, and that, in the event of some interruption of venting, as forexample, by closure or blocking of the venting instrumentality, thepressure will arise.

It is therefore an object of the present invention to prevent excessivepressure increase in the vehicle fuel tank by terminating the inflow offuel into the tank, automatically, as and when the pressure arises apredetermined amount above normal ambient.

This is accomplished preferably by means of the same lockout plungerwhich terminates the fuel supply in response to conclusion of thefilling operation, as, for example, by the creation of a vacuum-signalwhich is set up in response to the surge of liquid about the vent orso-called pressure tap.

This vastly simplifies the system by providing the additional functionwithout any apparent or material alteration in the size of the device.

It is accomplished in accordance with the present invention by causing acontrol pin, which dominates the action of the lockout plunger and whichpreviously responded only to the vacuum signal, to respond also topressures in excess of some predetermined value in the fuel tank toeffect a like termination of the operation.

In order to illustrate more or less diagrammatically one preferred formof the present invention, reference is made to the figures of thedrawing wherein FIG. 1 illustrates a dispensing nozzle embodying thepresent invention, coupled in sealing relationship with the inlet pipeof a fuel tank, parts of the assembly being broken away to show theinternal structure.

FIGS. 2 and 3 are a detailed elevation and views in sections of thecentral structure shown in FIG. 1 to illustrate positioning of the partsin response to (in FIG. 2) a vacuum signal, (FIG. 3) an excess pressurein the vehicle fuel tank.

FIG. 4 is a detailed sectional view taken on the line 44 of FIG. 1.

As will be apparent from the present figures, the present invention isintended for use during so-called tight seal fill operations, namelywherein the connection between the dispensing nozzle and the fuel tankis tightly or partially sealed.

To this end, therefore, FIG. 1 shows the inlet pipe of a fuel tank, notshown, provided with a coupling at its free end, comprising an annularcap 12 threaded on to the upper threaded extremity 14 of the pipe 10 asindicated. Spout 16 of the dispensing nozzle is provided with an annularcollar 18 which, as shown, may be provided with sealing means to enablea tightly or partially sealed connection. Insofar as the presentinvention is concerned, the exact structure of the seal is of nosignificance and may take any suitable form.

In general, the basic structure of the nozzle is shown by way of examplein U.S. Pat. No. 3,085,600, being formed of a casting 19 having acentral channel 20 and a main control valve 22, which is opened viavalve stern 23 by means of a lever 24, pivoted to a lockout plunger 26by fulcrum 28. A manually actuated latch 30 is normally adjusted to holdthe lever in open position. The lockout plunger 26 is locked in theposition shown by a plurality of steel balls 30, which are held againstshoulders formed on fixed housing 32 by a central control pin 34.

Control pin 34, in the conventional structure, is actuated by diaphragm36, in response to a vacuum signal as aforementioned, in an upwarddirection. This draws out the pin 34 from between the balls 30,permitting them to drop inwardly and releasing the lockout mechanism sothat a relatively heavy spring 38, which normally closes main poppetvalve 22, will drive down lever 24 and lockout plunger 26, together withfulcrum 28, closing the valve 22 and releasing the latch 30. The vacuumsignal is created in a continously acting venturi system 38, not shown,which communicates by passage 40, shown in dotted lines, with the spaceabove diaphragm 36. The vacuum signal, as is known, does not arise tooperative value until a vent or tap 42 which, thru conduit 44,communicates with the aforementioned venturi system, is closed by asplash or regurgitation of fuel around the vent 42.

In addition to the aforementioned conventional control system, thepresent invention provides a lower diaphragm 46, fixed to the samecentral pin 34 but normally separated from the upper diaphragm 36 by aspace 48 which is vented to atmosphere as at 50. Also, the space betweenthe two diaphragms 36 and 46 is largely occupied by an annular supportor shelf 52, which forms a rest for the greater part of the area of theupper diaphragm 36. Relatively light coil spring 54 tends to urge bothdiaphragm down into operative position. It is to be noted that while, asaforementioned, the space between the two diaphragms 36 and 46 is keptopen to atmosphere by a conduit 50, the space below diaphragm 46 isclosed by seals 63 and connects via duct or conduit 56 with tube 58which, like tube 58, passes down thru the interior of spout 16 and isvented (within the vehicle fuel tank) as at 60, preferably on the upperside of the spout and ordinarily above any back surge of fluid.

Accordingly, therefore, diaphragm 46 responds to predetermined, positivepressures in the vehicle tank (namely the fill pipe 10) which act uponthe lower surface thereof and against the atmospheric pressureprevailing on the upper side of the diaphragm in chamber 48.

Therefore, in normal operation, as filling proceeds to completion, withventing and with no untoward pressure increase in filler pipe 10, afinal rise of fluid around vent 42 will raise a vacuum signal in thespace above upper diaphragm 36, lifting the diaphragm to the positionshown in FIG. 2, thus retracting pin 34 upwardly and permitting balls 30to drop inwardly. This unlocks the plunger 26 which is driven downwardlyby the effect of spring 38, thru valve stem 23 and lever 24.

Diaphragm 46, being fixedly associated with diaphragm 36 by virtue of amutual connection to pin 34, is likewise drawn upwardly but not thru anyaction of its own.

However, reference to FIG. 3 of the drawing shows the position of theparts upon incidence of excessive pressure in the fuel tank. Thispressure, transmitted thru vent 60 and duct or conduit 58, raises thepressure below the lower or pressureresponsive diaphragm 46, forcing thediaphragm upwardly against atmospheric pressure normally existing in thespace 48 thereabove.

Again, by virtue of the mutual connection of the two diaphragms 36 and46 to the same central pin, the central portion of diaphragm 36 is alsoraised as shown. Due however to the shelf or support 52 only the centralportion of the upper diaphragm 36 is raised. This is of particularsignificance in view of the fact that an increase in pressuretransmitted via duct 58 will also be reflected in some measure by thepressure in duct 44. It, therefore, follows that as the pressure belowdiaphragm 46 is increased, there will be a similar increase of pressure(in spite of any differential attributable to the venturi action) abovediaphragm 36 so that without the support ledge 52 the force exertedagainst diaphragm 36 will tend to counteract the effect of the lowerdiaphragm. 46.

Since, however, in accordance with the present invention, only thecentral portion of diaphragm 36 need be flexed upwardly (as against thegreater area of the diaphragm 46 exposed to the increase in pressure)the net result will likewise be an upward movement or retraction of thepin 34, which, in substance, produces the net or resulting effect asbefore in respect to the lockout plunger on the remaining elements ofthe dispensing nozzle.

In brief, therefore, the present invention provides a mutuallypressure-responsive and vacuum-responsive lockout plunger mechanism forcontrol of the dispensing nozzle in response to both a vacuum signal asis conventional and a pressure signal, such as might result frommalfunction of a pressure filling system.

FIG. 4 indicates in general the provision of radial channels 62 on theupper surface of the annular shelf or plate 52 to limit any tendency ofthe upper diaphragm 36 to adhere thereto. On the other hand, the normalroughness of ordinary machining may be sufficient to accomplish thiseffect.

It is also important to observe that the annular ledge or support 52,previously mentioned, performs the very important function ofcounteracting the relative practical discrepancy which tends to occurbetween the two pressure phenomena involved. Stated in another way,inasmuch as the typical vehicle tank has very little pressure capacity,the pressure rise at which the present invention must necessarilyoperate is rather small, say in the order of not more than 2 to 4 inchesof mercury.

The typical vacuum signal, on the other hand, that is to say, thenegative pressure set up by closure of the vent 42, for-example, maynormally amount to several times this, as for example 8 inches ofmercury. Accordingly, therefore, it is advantageous to have a greatereffective area in the diaphragm 46 relative to the effective area of thediaphragm 36 at times when the device is being caused to operate inresponse to a pressure signal rather than a vacuum signal. Likewise, itis to be noted at this time that the upward force created by thesuperatmospheric pressure on the lower face of the diaphgram 46 needlift only the central portion of diaphgram 36 within the inner marginsof ledge 52.

I claim: 1. In a fuel dispensing nozzle comprising a spout (16) adaptedto sealably engage a fuel tank inlet, a flow control valve (22) beingnormally spring biased into a closed position to preclude fuel flowtherethrough, an end pivoted lever (24) actuatable to adjust said flowcontrol valve (22) to a fully open position, and a lockout plunger (26)having opposed ends, one end operably engaging the pivot end (28) ofsaid lever (24),

means forming a closure at said lock-out plunger (26) other end,

at least two diaphgrams (36, 46) sealably positioned in said meansforming said closure, and connected with said lock-out plunger (26) toform adjacent pressure and vacuum chambers within said closure,

first sensing means communicating said vacuum chamber with said nozzlespout whereby to urge said diaphragm (36) into said vacuum chamber andthereby displace said lock-out plunger (26) to adjust said flow controlvalve (22) to a partially open position at such time as said firstsensing means is immersed in fuel,

second sensing means communicated with said pressure chamber whereby totransmit pressure thereto from said nozzle spout, and thereby urge saidpressure sensitive diaphgram (46) into said pressure chamber to furtheradjust said lock-out plunger (26) and to permit said flow control valve(22) to move to the fully closed position.

2. In a fuel dispensing nozzle as defined in claim 1, wherein saidrespective pressure and vacuum sensing means includes; conduitscommunicated with the respective pressure and vacuum chambers, each ofsaid conduits having openings therein longitudinally spaced along saidnozzle spout.

3. In a fuel dispensing nozzle as defined in claim 2, wherein saidvacuum sensing conduit opening is disposed at a position downstream ofthe opening in said pressure sensing conduit.

4. In a fuel dispensing nozzle as defined in claim 2, including ventmeans in said closure means forming a vented space intermediate therespective diaphgrams (36, 46).

1. In a fuel dispensing nozzle comprising a spout (16) adapted tosealably engage a fuel tank Inlet, a flow control valve (22) beingnormally spring biased into a closed position to preclude fuel flowtherethrough, an end pivoted lever (24) actuatable to adjust said flowcontrol valve (22) to a fully open position, and a lock-out plunger (26)having opposed ends, one end operably engaging the pivot end (28) ofsaid lever (24), means forming a closure at said lock-out plunger (26)other end, at least two diaphgrams (36, 46) sealably positioned in saidmeans forming said closure, and connected with said lock-out plunger(26) to form adjacent pressure and vacuum chambers within said closure,first sensing means communicating said vacuum chamber with said nozzlespout whereby to urge said diaphragm (36) into said vacuum chamber andthereby displace said lock-out plunger (26) to adjust said flow controlvalve (22) to a partially open position at such time as said firstsensing means is immersed in fuel, second sensing means communicatedwith said pressure chamber whereby to transmit pressure thereto fromsaid nozzle spout, and thereby urge said pressure sensitive diaphgram(46) into said pressure chamber to further adjust said lock-out plunger(26) and to permit said flow control valve (22) to move to the fullyclosed position.
 2. In a fuel dispensing nozzle as defined in claim 1,wherein said respective pressure and vacuum sensing means includes;conduits communicated with the respective pressure and vacuum chambers,each of said conduits having openings therein longitudinally spacedalong said nozzle spout.
 3. In a fuel dispensing nozzle as defined inclaim 2, wherein said vacuum sensing conduit opening is disposed at aposition downstream of the opening in said pressure sensing conduit. 4.In a fuel dispensing nozzle as defined in claim 2, including vent meansin said closure means forming a vented space intermediate the respectivediaphgrams (36, 46).